Piston-ring former



April 13 1926. v 1,580,235

' v. Ds PRIMA PISTO RING FORMER Fild March 31. 1924 Ummlilh ,9.

ff-Cly Patented lApi. 13,

VINCENT DI yrnnvra, or DETROIT, irIIerIIGAN.y

rIsToNfnINGf nonnina. Y

f Appiicationrfnea Maren 31, 1924. senaiins.k 703,134.

To all iii/omit 77mg/l concern: Y

BeV itlmown that I,

VINCENTl DI PRIMA,

a citizen of the United States, residing at Detroit, in the county of l/Vaynexand vState of Michigan, have invented certain new and useful Improvements 1n Piston- Ring Formers, of which the following is a specification, reference being-had therein to the accompanying drawings.

In tlie'manufacture of castv 'piston rings it is necessary to prepare almold by using, among otherthings, pattern rings, andYV it is essential that the pattern rings be as perfect as possible in order that the cast rings will be as nearly true to required dimen sions as possible, to avoid considerable trimming or other machining. rings are ordinarily split The cast Vpiston same it has been the practice to set a plug betweenthe ends of a rpattern ring to hold the ring to proper size while being fastened to a support orl mold board.

The use of plugs or interposed members is very unsatisfactory because-a pattern ring cannot be heldto close dimensions, and as a substitute .for designed an expansible such plugs, I have member that may be placed in a pattern ring to maintain the ring expanded to exact dimensions while being fastened to a support or mold board. In consequence of the pattern ring being held to exactk dimensions it is obvious that the cast ring may closely' approach desired dimensions.

My expansible member includesv novel means for expanding it against the inner walls of the pattern ring to the thousandths part of an inch, and it is by virtue of such an expansible member that there may be a uniform production of castpiston rings.

My invention will fully be hereinafter -more described and then claimed, and reference will now the had to the drawing, where- Fig. 2 is a cross sectional view of the same;

Fig. 8 is a plan of the confronting ends of the expansible member;

Fig. L1 is a perspective viewshowing pattern rings mounted on a mold boardg. l

Fig. 5 is a longitudinal sectional view of a mold with a pattern ringin place;

Fig. 6 is a detail of expanding means view of a modified `form for the member, and

nulai expansible member 6- having its coii- F fronting ends 7 counterbored, as at 8. 'AC

and to Vproduce the l dimensions.

"whichpiston rings may' be cast- To hold tliepattern ring 1 to proper dimensions while'it isbeing fastenedto theA boardid, Iemploy a comparatively latanjacent the endsv of the annular member 7 are openings 9 for screws 10 or other fastening means employed for connecting the ends of the member 6 by a plate 11 VwhichV has slots 12 for the screws 10. On the screwsl() are washers 13 and by tightening the screws thevplate 11 may be attached to the ends of the member 6 to hold the member to desired Centrally ofthe plate 11 is a screw :socket 14 for a screw 15`having a nut or'head 16.

IThe inner end of the screwis provided with a pocket or recess 17 for a ballmember 18 which is adapted to seatlin the counterbore S" 8 at vthe confronting ends of the member 6. A suitable form of wrench or key 19 maybe' placed on the nut or head 16 of the screw 15 to rotate the screw and cause` the ball vmember 18 to expand or ldistend the con- 90V fronting ends ofthe members 6.

Instead of providing the member 6 with a counterbore and using the ball member 18 directly on the member 6, I may provide a Wedge member 20, as shownin Figs. 6 and 7, and have the ball member'18 engage in the wedge member. I consider the wedge member 20 to be the mechanical equivalent of theV ball member 18 or any member that may be interposedbetween the ends of the expansible member 6 to cause separation of the ends of said member.

' With the screws. 10 loose andthe expansible member 16 set in the pattern ring 1, the screw 15 may be adjusted -to expand the member 6 to the thousandths part of an inch, such expansion ofthe member separating the ends lof the 'pattern ring 1 until the patj lvl place marks on the expansible member 6 and the pattern ring l so that the pattern ring may bey correctly positioned relative to the expansible member 6 to be equally distended at proper places by theV expansible'member. After the screw 15 is adjusted to bri-ngr lthe pattern ring l to proper form, the, screws l0 can be tightened to hold the expansible member 6 to its set dimension. The pattern ring, l can then be fastened to th'e'mold board l and the expansible member 6 used for holding other pattern rings to form, so that there will be uniformity in the production oit cast piston rings in a mold.

lith the plate ll adjustable relative to the ends ot the member 6 it is obvious that my expansible member may be used in the production of 'pistonl rings of various sizes, and While in the drawing there is illustrated the preferred embodiment lof my invention, it is to be understood ythat the structural elements are susceptible to such Variations and modifications as fall Within the scope ot the appended claims.

l/Vhat l claiml is Y l. Means for adjusting and holding a pattern piston ring to form While being attached to a support for the production oi' cast piston rings, comprising an expansible member adapted to be placed in a pattern ring` and expanded against the inner Wall of the pattern ring, Vsaid expansible member having counterbored ends, a ball member engaging; the connterbored ends of said member, a plate articulating the ends of said member, and means on said plate engaging said ball member to cause expansion ot said expansible member.

2. Means 'for adj usting and holding a pattern piston ring to form While being attached to a support for the production ot cast pis ton rings7 comprising an vezgpansibie member adapted to be placed in a pattern ring and expanded vagainst the inner Wall of the palttei'n ring, a lplate carried by said expansible member, means carried by said plate for eX- panding said'member, and'means holding; said plate, relative to said member to permit of said plate being tired after said mr'ginbei` hasV been expanded@ Y In testimony whereof I atiix my signature.

VINCENT DI ren/n. 

